Respiration in plants

Fumaric acid is a naturally occurring sour-tasting compound found in many plants such as Fumaria officinalis L. (Fumariaceae), Boletus scaber Bull. (Boletaceae), and Fames igniaries (Fries) Kickx. (Pluporaceae). It is an essential component for respiration in plant and animal tissues. It is produced by fermentation with mold, such as Rhizopus nigricans, or by chemical synthesis. It is also used in soft drinks and ice cream and as an acidulant along with citric acid. 

Elevation of the ethanol content occurs during the maturation stage of fruit development when acidity declines, total solids increase, and the flavor compounds accumulate to characteristically ripe levels. Since ethanol is a normal product of anaerobic respiration in plants, its accumulation signals a change in the pathway of energy metabolism. This summary of research on the control of ethanol accumulation in citrus fruit describes an approach to identify the role of energy metabolism in the bioregulation of maturation. 

The cytochromes are probably the most important class of electron-transfer proteins. They are involved in photosynthesis, embedded in the thylakoid membranes of chloroplasts. They are also involved in the opposite process of cellular respiration in plants and animals, which occurs in the membranes of mitochondria. ... 

Mitochondria from maize leaves do in fact respond to a series of strobilurins, but are in this case less sensitive than mitochondria from non-plant species (yeast, Botrytis, rat, house fly) [59]. Note that, generally, inhibition of mitochondrial respiration in plants ( dark respiration ) does not lead to severe undesired influences on plant physiology. 

Respiration in plants is taken to include all the phenomenon of dissimilation, the characteristics of which are the breaking down of complex substances into simpler ones with a consequent release of... 

Potassium [7440-09-7] K, is the third, element ia the aLkaU metal series. The name designation for the element is derived from potash, a potassium mineral the symbol from the German name kalium, which comes from the Arabic qili, a plant. The ashes of these plants al qili) were the historical source of potash for preparing fertilisers (qv) or gun powder. Potassium ions, essential to plants and animals, play a key role in carbohydrate metaboHsm in plants. In animals, potassium ions promote glycolysis, Hpolysis, tissue respiration, and the synthesis of proteins (qv) and acetylcholine. Potassium ions are also beheved to function in regulating blood pressure. 

Potassium is required for enzyme activity in a few special cases, the most widely studied example of which is the enzyme pymvate kinase. In plants it is required for protein and starch synthesis. Potassium is also involved in water and nutrient transport within and into the plant, and has a role in photosynthesis. Although sodium and potassium are similar in their inorganic chemical behavior, these ions are different in their physiological activities. In fact, their functions are often mutually antagonistic. For example, increases both the respiration rate in muscle tissue and the rate of protein synthesis, whereas inhibits both processes (42). 

Fig. 11-1. Mean monthly concentrations of atmospheric C02at Mauna Loa. The yearly oscillation is explained mainly by the annual cycle of photosynthesis and respiration of plants in the Northern Hemisphere. Source Lindzen (2).

Like all matter, carbon can neither be created nor destroyed it can just be moved from one place to another. The carbon cycle depicts the various places where carbon can be found. Carbon occurs in the atmosphere, in the ocean, in plants and animals, and in fossil fuels. Carbon can be moved from the atmosphere into either producers (through the process of photosynthesis) or the ocean (through the process of diffusion). Some producers will become fossil fuels, and some will be eaten by either consumers or decomposers. The carbon is returned to the atmosphere when consumers respire, when fossil fuels are burned, and when plants are burned in a fire. The amount of carbon in the atmosphere can be changed by increasing or decreasing rates of photosynthesis, use of fossil fuels, and number of fires. 

Fig. 10-13. The links between the cycling of C, N, and O2 are indicated. Total primary production is composed of two parts. The production driven by new nutrient input to the euphotic zone is called new production (Dugdale and Goering, 1967). New production is mainly in the form of the upward flux of nitrate from below but river and atmospheric input and nitrogen fixation (Karl et al, 1997) are other possible sources. Other forms of nitrogen such as nitrite, ammonia, and urea may also be important under certain situations. The "new" nitrate is used to produce plankton protoplasm and oxygen according to the RKR equation. Some of the plant material produced is respired in the euphotic zone due to the combined efforts...

Brix, H. (1962). The effect of water stress on the rates of photosynthesis and respiration in tomato plants and loblolly pine seedlings. Physiologia Plantarum, IS, 10-20. 

J. Swinnen, Evaluation of the use of a model rhizodeposition technique to separate root and microbial respiration in. soil. Plant Soil /65 89 (1996). 

Three processes that take place in living organisms - respiration in animals and plants, photosynthesis only in plants, and the precipitation of solids by some aquatic animals - have altered the primeval composition of the outer solid, liquid, and gaseous layers of the earth. Respiration consumes oxygen from the atmosphere and creates carbon dioxide. Photosynthesis, which does the opposite (consumes carbon dioxide and releases oxygen), has... 

The partial pressure of C02 in the soil air controls the concentration of both dissolved C02 and undissociated carbonic acid. At 0.003 atm of C02 (g) as a reference level for soils, [H2C03°] is about 1.04 x 10 4 M (Lindsay, 1979). At a normal atmospheric level of 0.0003 atm C02 (g), [H2C03°] is approximately 1.04 x 10 5 M. In most soils, C02 (g) is higher than in the atmosphere. C02 is released from soil and plant root respiration. In flooded soils, C02 (g) partial pressure increases to 0.01-0.3 atm, about 1000-fold higher than normal upland soils due to strong microbiological activity (Lindsay, 1979). 

Azcon-Bieto, J., J. Murillo, and J. Penuelas. 1987. Cyanide-resistant respiration in photosynthetic organs of freshwater aquatic plants. Plant Physiol. 84 701-706. 

Mitochondrial respiration, insecticides and acaricides acting on, 14 348-349 Mitosis, in plants, 13 302 Mitotic entry inhibitors, 13 302-303 Mitotic sequence, disruption of,... 

Rates of respiration in different root tissues. The formation of aerenchyma decreases the respiratory O2 demand per unit root volume because there is less respiring root tissue. Also, some plants can tolerate a degree of anoxia in parts of the root, which substantially reduces the O2 demand per unit root volume. 

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